Liquid spray device and cutting method

ABSTRACT

A liquid spray device, comprising a container ( 1 ), a spray injection nozzle ( 2 ) for injecting oil spray into the container ( 1 ), a spray feeding path ( 5 ) for feeding oil spray in the container ( 1 ) to the outside of the container ( 1 ), oil ( 11 ) stored in the container ( 1 ), a gas exhaust port provided in the oil ( 11 ) by discharging gas into the oil ( 11 ), whereby the flow velocity of the oil spray in the spray feeding path can be increased and the amount of oil spray can be increased because an internal pressure of the container can be increased and an oil spray different from the oil spray from the spray injection nozzle can be produced.

TECHNICAL FIELD

The present invention relates to a liquid spray device for feeding spray(liquid particulates) in a container to spray liquid to a target objectand a cutting method using the same. More particularly, the presentinvention relates to a liquid spray device for supplying a cuttingmember of a machine tool, for example, a machining center, a grindingmachine, a turning machine, or the like, with a cutting oil and to acutting method using the same.

BACKGROUND ART

Hitherto, during machining, oil is sprayed to a target object, forexample, a work piece or a tool, etc., in order to enhance the machiningaccuracy or to extend the life of tools. In a method of directlyspraying liquid oil to the target object, the amount to be sprayedbecomes too large, so that it takes a long time to remove excess oil,thus reducing the productivity. Furthermore, since the excess oilscatters around the device, it has been necessary to prevent the workingenvironment from being contaminated.

When oil is sprayed in the form of oil droplets, since a machiningoperation can be performed with only the necessary minimum amount ofoil, it is possible not only to improve the process accuracy orproductivity, but also to improve the working environment, thussimplifying plant and equipment. JP5-92596U proposes one example of adevice capable of spraying oil in the form of oil droplets.

However, in the above-mentioned oil supplying device, it is necessary toprovide a spray producing part with a casing for an oil dropping part, apath for fast-speed gas, a Venturi nozzle, and the like. Furthermore, apump and an oil vessel are formed separately from the main body, thusmaking the structure of the spray device complicated.

Furthermore, in the above-mentioned oil supplying device, an internalpressure of the main body is dependent upon a primary supply pressureand a hole diameter (a cross-sectional area) of a tip spray injectionpart. Consequently, as the hole diameter of the spray injecting part ischanged, the internal pressure of the main body changes accordingly.Therefore, when, for example, a tool provided with a discharging port isused as the spray injection part, if the tool is replaced with onehaving a smaller hole diameter, the internal pressure of the main bodyis increased. In this case, the flow velocity of spray injection can besecured without any problems. However, since the difference between theprimary supply pressure and the internal pressure of the main body isreduced, a sufficient amount of spray may not be produced effectively ata spray production part.

On the contrary, if the tool is replaced with one having a larger holediameter, the internal pressure of the main body is reduced. In thiscase, it is possible to secure the difference between the primary supplypressure and the internal pressure of the main body. Therefore, there isno problem in producing spray effectively. However, occasionally, theflow velocity of injection cannot be secured sufficiently. Actually, anumber of production plants employ unmanned operation. Therefore, it isimpossible to adjust the supply pressure every time the hole diameter ofinjection is changed.

DISCLOSURE OF INVENTION

It is an object of the present invention to provide a liquid spraydevice capable of reliably producing a fine spray stably with a simplestructure and of securing a flow velocity of injecting spray and acutting method using the same.

In order to attain the above-mentioned object, a first liquid spraydevice according to the present invention includes a container, a sprayinjection nozzle for injecting oil spray into the container, a sprayfeeding path for feeding oil spray in the container to the outside ofthe container, wherein liquid is stored in the container, and anunder-liquid nozzle having a gas exhaust port in the liquid andproducing spray by supplying gas into the liquid is provided.

With such a liquid spray device, the use of the under-liquid nozzle canenhance the internal pressure of the container and produce spray inaddition to the spray produced by the spray injection nozzle. Thus, itis possible to increase the flow velocity of spray at the exit of thespray feeding path and to increase the amount of spray.

It is preferable in the first liquid spray device that most of theinjected spray flow from the spray injection nozzle is allowed to strikethe wall face of the container before being fed to the spray feedingpath. With such a preferred liquid spray device, since oil spray havinga large diameter or oil droplet is easily attached to the wall face, itis possible to prevent the oil spray having a large diameter or oildroplet from entering the spray feeding pipe.

Furthermore, it is preferable that the wall face is a liquid surface ofthe liquid. With such a liquid spray device, since oil spray having alarge diameter or oil droplet is easily absorbed by the liquid surfacewhen striking the liquid surface, it is possible to prevent the oilspray having a large diameter or oil droplet from entering the sprayfeeding pipe.

Furthermore, it is preferable that the liquid spray device furtherincludes a pressure controlling means for keeping the pressure in thecontainer constant in a path for supplying the gas to the under-liquidnozzle. When the internal pressure of the container is constant, thedifference between the primary pressure of the gas supplied to thecontainer and the internal pressure of the container becomes constant,the flow velocity of the gas in the container for spraying is alsoconstant, and thus stable production of spray can be realized.Furthermore, also at the discharging part, since the constant flowvelocity can be secured, it is possible to discharge oil spray byconverting the oil spray into the oil droplets.

Furthermore, it is preferable that the liquid spray device furtherincludes a gas discharge nozzle having a tip in the air inside thecontainer and discharging gas. With such a liquid spray device, sincethe internal pressure of the container can be increased, it is possibleto increase the flow velocity at the exit part of the spray feedingpath.

Furthermore, it is preferable that the liquid spray device furtherincludes a pressure controlling means for keeping the pressure in thecontainer constant for feeding gas into a path for supplying the gas tothe gas discharge nozzle. If the internal pressure for feeding gas intothe container is constant, the difference between the primary pressurein the container and the internal pressure of the container becomesconstant. As a result, the flow velocity of the gas for producing sprayin the container is also constant, thus realizing the stable productionof spray. Furthermore, it is possible to obtain the constant flowvelocity also at the discharge part, and it is possible to dischargespray in the form of oil droplets.

Furthermore, it is preferable that a tip-tapered discharge part isconnected to the tip of the spray feeding path. With such a liquid spraydevice, the flow velocity of spray at the discharge part is increased,and it is possible to take out the spray in the form of oil droplets.

Furthermore, it is preferable that gas and liquid are fed to the sprayinjection nozzle, and the spray is injected into the container by mixingthe gas and the liquid in the spray injection nozzle.

Furthermore it is preferable that the liquid stored in the containerflows into a liquid supply means and the liquid discharged from theliquid supply means is fed to the spray injection nozzle. With such aliquid spray device, it is not necessary to provide an oil tankseparately, so that it is possible to circulate the liquid in thecontainer effectively.

Furthermore, it is preferable that the liquid supply means is a liquidpump.

Furthermore, it is preferable that the liquid supply means is a siphontube having the tip portion in the liquid stored in the container andcapable of siphoning up the liquid stored in the container.

Furthermore, it is preferable that the liquid spray device furtherincludes a pressure control means for keeping the pressure in thecontainer constant in a path for supplying the gas to the sprayinjection nozzle. When the internal pressure of the container isconstant, the difference between the primary pressure of the gassupplied to the container and the internal pressure of the container isconstant, the flow velocity of the gas in the container for spraying isalso constant, and thus stable production of spray can be realized.Furthermore, also at the discharge part, the constant flow velocity canbe secured, and it is possible to discharge oil spray by converting oilspray into oil droplets.

Next, according to a second liquid spray device of the presentinvention, the liquid spray device includes a container, a sprayinjection nozzle for injecting spray into the container, and a sprayfeeding path for feeding the spray in the container to the outside ofthe container, wherein most of the injected spray flow from the sprayinjection nozzle is allowed to strike the wall face in the containerbefore being fed to the spray feeding path.

According to such a liquid spray device, since oil spray having a largediameter or oil droplets are attached easily to the wall face when theystrike the wall face, it is possible to prevent the oil spray having alarge diameter or oil droplets from entering the spray feeding pipe.

It is preferable in the second liquid spray device that the inside ofthe container is divided into an upper space and a lower space by thewall face, and the injection port of the spray injection nozzle islocated in the lower space.

According to such a liquid spray device, since oil spray having a largediameter or oil droplets are attached easily to the wall face when theystrike the wall face, and most of the attached spray and droplets dropto the lower part of the container by gravity. Therefore, most of thespray or droplets fed to the upper space is fine spray. Thus, it ispossible to prevent oil spray having a large diameter or oil dropletfrom entering the spray feeding pipe.

Furthermore, it is preferable that the inside of the container isdivided into an upper space and a lower space by the wall face, and theinjection port of the spray injection nozzle is located in the upperspace.

According to such a liquid spray device, since most of oil spray havinga large diameter or oil droplet is attached to the wall face, when itstrikes the wall face, most of the attached spray and droplets drop tothe lower part of the container by gravity along the wall face.Therefore, most of the spray or droplets fed to the upper space is finespray. Thus, it is possible to prevent oil spray having a large diameteror oil droplet from entering the spray feeding pipe.

Furthermore, it is preferable that the wall face is the inner wall faceof a dome member opening downward. With such a liquid spray device, itis easy to drop spray having a large diameter or droplets to the lowerspace, that is, a lower part of the container.

Furthermore, it is preferable that the wall face is the outer wall faceof a dome member opening downward. With such a liquid spray device, itis easy to drop spray having a large diameter or droplets to the lowerspace, that is, a lower part of the container.

Furthermore, it is preferable that the wall face is a liquid surface ofthe liquid stored in the container. With such a liquid spray device,since oil spray having a large diameter or droplets are easily attachedto the wall face when they strike the face, it is possible to preventthe oil spray having a large diameter or droplets from entering thespray feeding pipe.

Furthermore, it is preferable that an injected spray flow feeding pathis formed on the wall face, and most of the injected spray flow from thespray injection nozzle can be taken out directly to the outside of thecontainer by opening a valve connecting to the injected spray flowfeeding path.

With such a liquid spray device, in a case where the screening of theparticle size of spray is not required, the injected spray flow from thespray injection nozzle can be taken out to the outside of the containerdirectly.

Furthermore, it is preferable that the injected spray flow, afterstriking the wall face and before being fed to the spray feeding path,strikes another wall face formed separately from the wall face. Withsuch a liquid spray device, it is possible to prevent the oil sprayhaving a large diameter or oil droplets from entering the spray feedingpipe thoroughly.

Furthermore, it is preferable that the liquid spray device furtherincludes a gas discharge nozzle having a tip in the air inside thecontainer and discharging gas. With such a liquid spray device, sincethe internal pressure of the container can be increased, it is possibleto increase the flow velocity of the spray at the exit part of the sprayfeeding path.

Furthermore, it is preferable that the liquid spray device furtherincludes a pressure control means for keeping the pressure in thecontainer constant in the path for supplying the gas to the gasdischarge nozzle. When the internal pressure of the container forspraying is constant, the difference between the primary pressure of thegas supplied to the container and the internal pressure of the containeris constant, the flow velocity of the gas in the container for producingspray is also constant, and thus spray can be produced stably.Furthermore, also at the discharging part, the constant flow velocitycan be secured, and it is possible to discharge oil by converting oilspray into the oil droplets.

Furthermore, it is preferable that a tip-tapered discharge part isconnected to the tip of the spray feeding path. With such a liquid spraydevice, the flow velocity is increased at the injection part, so that itis possible to take out oil by converting oil spray into droplets.

Furthermore, it is preferable that gas and liquid are fed to the sprayinjection nozzle, and the spray is injected into the container by mixingthe gas and the liquid in the spray injection nozzle.

Furthermore, it is preferable that the liquid stored in the containerflows into a liquid supply means and the liquid supplied from the liquidsupply means is fed to the spray injection nozzle. With such a liquidspray device, an oil tank is not provided separately, thus circulatingthe liquid in the container efficiently.

Furthermore, it is preferable that the liquid supply means is a liquidpump.

Furthermore, it is preferable that the liquid supply means is a siphontube having a tip portion in the liquid stored in the container andcapable of siphoning up the liquid stored in the container.

Furthermore, it is preferable that the liquid spray device furtherincludes a pressure control means for keeping the pressure in thecontainer constant in a path for supplying the gas to the sprayinjection nozzle. When the internal pressure of the container isconstant, the difference between the primary pressure of the gassupplied to the container and the internal pressure of the container isconstant, the flow velocity of the gas in the container for producingspray is also constant, and thus spray can be produced stably.Furthermore, also at the discharging part, the constant flow velocitycan be secured, and it is possible to discharge oil by converting oilspray into the oil droplets.

Next, according to a third liquid spray device of the present invention,spray in a container passes through the spray feeding path and is fed tothe outside of the container by pressure of the gas supplied into thecontainer, and a pressure control means keeps the pressure in thecontainer constant.

With such a liquid spray device, spray having a large diameter can betrapped in the container constantly. The feeding of spray has anexcellent fast-response property. It is possible to keep the internalpressure of the container constant. Therefore, the difference betweenthe primary pressure of the gas supplying to the gas and the internalpressure of the container is constant and the flow velocity of gas forproducing spray is also constant, and thus spray can be produced stably.Furthermore, since it is possible to obtain the constant flow velocityat the injection part, it is possible to inject the spray in the form ofoil droplets and to prevent the flow velocity of the spray fromchanging. As a result, the amount of discharge spray can be made stable.

It is preferable in the above-mentioned third liquid spray device of thepresent invention that the spray is injected from the spray injectionnozzle for injecting the spray into the container, gas and liquid arefed to the spray injection nozzle, and the spray is injected into thecontainer by mixing the gas and the liquid in the spray injectionnozzle.

Furthermore, it is preferable that the liquid spray device includes thepressure control means in the path for supplying the gas to the sprayinjection nozzle.

Furthermore, it is preferable that liquid is stored in the container,and an under-liquid nozzle having a gas exhaust port in the liquid andproducing the spray from liquid by supplying gas to the liquid by theunder-liquid nozzle is provided.

Furthermore, it is preferable that the liquid spray device furtherincludes a pressure control means in a path for supplying the gas to theunder-liquid nozzle.

Furthermore, it is preferable that the pressure control means has apressure regulating valve connecting to the gas supplying path, closesthe pressure regulating valve to stop supplying the gas when thepressure in the container is increased and reaches a set value, andopens the pressure regulating valve to resume gas supply when thepressure in the container drops to the predetermined pressure. With sucha liquid spray device, since the structure is simple, the cost can beminimized, and the attachment work is simplified.

Furthermore, it is preferable that the set value can be changed. Such aliquid spray device can be used in different manners depending upon theapplications of use.

Furthermore, it is preferable that the pressure control means has anelectromagnetic valve connecting to the gas supplying path and apressure switch having a pressure detection part located in thecontainer, wherein when the pressure in the container is increased andreaches the upper limit of the set value, the pressure switch closes theelectromagnetic valve to stop supplying gas, and when the pressure inthe container drops to the lower limit of the set value, the pressureswitch opens the electromagnetic valve to re-start to supply the gas.With such a liquid spray device, the operation becomes more reliable,and the accuracy in the pressure control can be enhanced.

Furthermore, it is preferable that the pressure switch has a pluralityof combinations of different upper limit set values and lower limit setvalues and can be switched between the combinations. With such apressure switch, the device can be used separately for several purposes,for example, for cutting and for air blowing.

Furthermore, it is preferable that the pressure control means has avalve provided in the gas supplying path and a pressure sensor fordetecting the pressure of the gas after passing through the valve, and acontrol part, wherein the detection pressure detected by the pressuresensor is converted into electric signals and the electric signals areprocessed arithmetically at the control part, and the control partproduces a signal to close the valve so as to stop supplying the gaswhen it judges that the detection pressure reaches the upper limit ofthe set value, and the control part produces a signal to open the valveso as to resume gas supply when it judges that the detection pressurereaches the lower limit of the set value. With such a liquid spraydevice, the operation is more reliable, and the accuracy in the pressurecontrol can be enhanced.

Furthermore, it is preferable that the pressure sensor is located in thecontainer.

Furthermore, it is preferable that the pressure sensor is locatedbetween the valve and the container in the gas supplying path.

Furthermore, it is preferable that the pressure sensor is located in thespray feeding path.

Furthermore, it is preferable that the upper limit and lower limit setvalues can be changed. With such a liquid spray device, the device canbe used separately for several purposes, for example, for cutting andfor air blowing.

Furthermore, it is preferable that a tip-tapered discharging part isconnected to the tip of the spray feeding path. With such a liquid spraydevice, since the flow velocity of spray is increased at the spraydischarge part, spray can be taken out in the form of droplets.

Next, according to a first cutting method of the present invention, acutting method includes attaching a liquid spray device to an oilsupplying part of a machine tool, the liquid spray device including acontainer, a spray injection nozzle for injecting oil spray into thecontainer, a spray feeding path for feeding oil spray in the containerto the outside of the container, wherein the oil is stored in thecontainer, and an under-liquid nozzle having a gas exhaust port producesspray by discharging gas into the oil; and cutting the target object tobe processed by supplying the spray to a cutting member of the machinetool.

According to the above-mentioned cutting method, since the spray issupplied to the target object to be processed, the spraying amount canbe minimized, thus improving the productivity and preventing theoperation environment from being contaminated. Furthermore, since theliquid spray device is provided with the under-liquid nozzle, theinternal pressure in the container can be increased, and another spraycan be produced in addition to the spray from the spray injectionnozzle. Therefore, the flow velocity of the spray at the exit part ofthe spray feeding path can be increased and the amount of spray can beincreased.

It is preferable in the above-mentioned first cutting method that mostof the injected spray flow from the spray injection nozzle is allowed tostrike the wall face of the container before being fed to the sprayinjection path. According to the above-mentioned cutting method, sincespray having a large diameter or droplets are attached easily to thewall face, it is possible to prevent the oil spray having a largediameter or droplets from entering the spray feeding pipe.

Next, according to a second cutting method, a cutting method includesattaching a liquid spray device to an oil supplying part of a machinetool, the liquid spray device including a container, a spray injectionnozzle for injecting oil spray into the container, a spray feeding pathfor feeding oil spray in the container to the outside of the container,wherein most of the spray from the injection nozzle is allowed to strikea wall face in the container before being fed to the spray feeding path;and cutting the target object to be processed by supplying the spray toa cutting member of the machine tool.

According to the above-mentioned cutting method, since the spray issupplied to the target object to be processed, the spraying amount canbe minimized, thus improving the productivity and preventing theoperation environment from being contaminated. Since spray having alarge diameter or droplets are attached easily to the wall face, it ispossible to prevent the oil spray having a large diameter or dropletsfrom entering the spray feeding pipe.

It is preferable in the pressure control means has an electromagneticvalve connecting to the gas supplying path and a pressure switch havinga pressure detection part located in the container, wherein when thepressure in the container is increased and reaches the upper limit ofthe set value, the pressure switch closes the electromagnetic valve tostop supplying gas, and when the pressure in the container drops to thelower limit of the set value, the pressure switch opens theelectromagnetic valve to resume gas supply. In the second cuttingmethod, the inside of the container is divided into an upper space and alower space by the wall face, in which the injection port of the sprayinjection nozzle is located in the lower space. According to theabove-mentioned cutting method spray having a large diameter or dropletsare attached easily to the wall face. Most of the attached spray ordroplets drop by gravity into the lower space, that is, the lower partof the container, so that most of the spray fed to the upper space isfine spray. Thus, it is possible to prevent the spray having a largediameter or droplets from being fed to the spray feeding pipe.

Furthermore, it is preferable that the container is divided into anupper space and a lower space by the wall face, in which the injectionport of the spray injection nozzle is located in the upper space.

According to the above-mentioned cutting method, the spray having alarge diameter or droplets, when they strike the wall face, are attachedto the wall face, or drop along the wall face downward to the lowerspace. Therefore, most of the spray fed to the upper space of thecontainer is fine spray. It is possible to prevent the spray having alarge diameter or droplets from being fed to the spray feeding pipe.

Next, according to a third cutting method of the present invention, acutting method includes attaching a spray device to an oil supplyingpart of the machining tool, wherein in the spray device, the spray inthe container passes through the spray feeding path and is fed to theoutside of the container by a gas pressure of the gas supplied into thecontainer, and a pressure control means for keeping the pressure insidethe container constant is provided; and cutting the target object to beprocessed by supplying a cutting member of the machining tool with thespray.

According to the above-mentioned cutting method, since the spray issupplied to the target object to be processed, the spraying amount canbe minimized, thus improving the productivity and preventing theoperation environment from being contaminated. With the above-mentionedliquid spray device, spray having a large diameter can be trapped in thecontainer. The feeding of the spray has an excellent fast-responseproperty. It is possible to keep the internal pressure of the containerconstant. Therefore, the difference between the primary pressure of thegas supplying to the container and the internal pressure of thecontainer is constant and the flow velocity of gas for producing sprayis constant, thus realizing the stable production of spray. Furthermore,it is possible to obtain the constant flow velocity at the dischargepart, it is possible to inject the spray in the form of the oil dropletsand to prevent the flow velocity of the spray from changing. As aresult, the amount of discharge spray can be made stable.

It is preferable in the third cutting method that the pressure controlmeans has a pressure regulating valve connecting to the gas supplyingpath, and wherein the pressure regulating valve is closed so as to stopsupplying the gas when the pressure in the container is increased to theset value, and the pressure regulating valve is opened so as to resumegas supply when the pressure in the container drops to the predeterminedpressure.

According to the above-mentioned cutting method, the structure of theliquid spray device is simplified, and it is possible to minimize thecost. The attachment operation is easy.

Furthermore, it is preferable that the pressure control means has anelectromagnetic valve connecting to the gas supply path and a pressureswitch having a pressure detection part located in the container, andwherein the pressure switch closes the electromagnetic valve to stopsupplying the gas when the pressure in the container is increased to theset value, and the pressure switch opens the electromagnetic valve toresume gas supply when the pressure in the container drops to thepredetermined pressure. As mentioned above, the operation of the liquidspray device can be made reliable, thus enhancing the accuracy of thepressure control.

Furthermore, it is preferable that the pressure control means includes avalve provided in the gas supplying path, a pressure sensor fordetecting the pressure of the gas after passing through the valve and acontrol part, wherein the detection pressure detected by the pressuresensor is converted into electric signals and the electric signals areprocessed arithmetically at the control part, wherein the control partsends a signal to close the valve so as to stop the gas supply when itjudges that the detection pressure reaches the upper limit of the setvalue, and the control part sends a signal to open the valve so as toresume gas supply when it judges that the detection pressure reaches thelower limit set value. According to the above-mentioned cutting method,it is possible to obtain more reliable operation and to enhance theaccuracy in the pressure control.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a vertical cross sectional view showing a liquid spray devicein Embodiment 1 according to the present invention.

FIG. 2 is a horizontal cross sectional view showing a liquid spraydevice in Embodiment 2 according to the present invention.

FIG. 3 is a vertical cross sectional view showing a liquid spray devicein Embodiment 3 according to the present invention.

FIG. 4 is a vertical cross sectional view showing a liquid spray devicein Embodiment 4 according to the present invention.

FIG. 5 is a vertical cross sectional view showing a liquid spray devicein Embodiment 5 according to the present invention.

FIG. 6 is a vertical cross sectional view showing a liquid spray devicein Embodiment 6 according to the present invention.

FIG. 7 is a vertical cross sectional view showing a liquid spray devicein Embodiment 7 according to the present invention.

FIG. 8(a) shows a pressure control circuit in Embodiment 8 according tothe present invention.

FIG. 8(b) shows a pressure control circuit in Embodiment 9 according tothe present invention.

FIG. 8(c) shows a pressure control circuit in Embodiment 10 according tothe present invention.

FIG. 9 shows a pressure control circuit in Embodiment 11 according tothe present invention.

BEST MODE OF CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described by way ofembodiments with reference to drawings. In each embodiment, the liquidspray device according to the present invention is used as an oil supplydevice.

Embodiment 1

FIG. 1 is a vertical cross sectional view showing a liquid spray deviceaccording to Embodiment 1. Reference numeral 1 denotes a container. Thecontainer 1 is provided with a spray injection nozzle 2, a gas injectionnozzle 3, an under-liquid nozzle 4 and a spray feeding pipe 5.

The spray injection nozzle 2 has a dual structure formed of a gas tube 6and an oil tube 7. The oil tube 7 passes through the gas tube 6. The gastube 6 is connected to a gas source 8 and the flow rate of injecting gascan be regulated by a gas flow rate regulating valve 9 a. The oil tube 7is connected to the oil pump 10. For the gas discharged from the gassource 8, for example, air is used.

Furthermore, at the tip of the spray injection nozzle 2 inside thecontainer 1, the tip of the oil tube 7 enters the inside of the gas tube6. At the nozzle tip 6 a, oil supplied from the oil pump 10 and gassupplied from the gas source 8 are mixed with each other, and thus oilspray is produced and injected into the container 1.

The gas injection nozzle 3 supplies the container 1 with gas and isconnected to the gas source 8 and the flow rate of injecting gas can beregulated by a gas flow rate regulating valve 9 b.

The under-liquid nozzle 4 is immersed in oil 11 filled in the container1 in a predetermined amount. The under-liquid nozzle 4 is connected tothe gas source 8 and the flow rate of injecting gas can be regulated bya gas flow rate regulating valve 9 c. When the gas is injected into theoil 11 from the under-liquid nozzle 4, the oil 11 is entrained by theinjected gas and splashed and entrained from the liquid surface of theoil as an oil spray.

The spray feeding pipe 5 feeds the spray in the container 1 to theoutside of the container 1. The spray feeding pipe 5 is connected to aspray feeding outside pipe 12 for feeding the oil spray to a targetobject. The tip side of the spray feeding outside pipe 12 is connectedto a tip-tapered discharge part 13.

For example, the spray feeding outside pipe 12 can be used as follows:the spray feeding outside pipe 12 is connected to a spindle with an oilhole of the machining center; and a drill is attached to the spindlehaving an oil hole as a discharge part 13. The drill has a dischargepart having a smaller hole diameter at the tip thereof Furthermore, itis possible to fill the oil 11 inside the container 1 from an oil supplyport 15 by removing an oil supply cap 14. The oil 11 flows into the pump10 through a supply port 16. The following is an explanation of theoperation in which the oil spray inside the container 1 flows to theoutside of the container. Both oil spray injected from the nozzle tip 6a of the spray injection nozzle 2 and oil spray produced from the liquidsurface of the oil 11 by the under-liquid nozzle 4 can be supplied intothe container 1.

First, the case in which the oil spray is supplied into the container 1only by the spray injection nozzle 2 by stopping the gas supply from theunder-liquid nozzle 4 is explained. The particle size of the oil sprayinjected from the nozzle tip portion 6 a ranges from small to large.

Furthermore, oil is injected not only in the form of spray but also inthe form of oil droplets. Oil spray having a large particle size or oildroplets easily drops by gravity. On the other hand, fine oil spraydrops by gravity relatively slowly and resides in the container for along time. Fine oil spray herein denotes oil spray that is capable ofdrifting in the air in the form of fume.

The air pressure from the spray injection nozzle 2 is applied to theinside of the container 1, so that fine oil spray residing in thecontainer 1 is affected by the pressure applied and moves in thedirection shown by an arrow a and is fed to the spray feeding pipe 5.

Since the oil spray having a large particle size or oil droplets tendsto drop by gravity toward the liquid surface of the oil 11, it is hardlyaffected by the air pressure. Therefore, such an oil spray having alarge particle size or oil droplets does not flow into the spray feedingoutside pipe 12 easily.

As mentioned above, since most of the oil spray fed to the spray feedingoutside pipe 12 is fine oil spray, it can be fed rapidly and hardly beattached to the inner wall face of the pipe. Therefore, even if thelength to the target object becomes long and the pipe length of thefeeding pipe is increased, it is possible to allow the oil spray to passthrough the feeding pipe in a short time.

The flow velocity of the oil spray is increased after passing throughthe spray feeding path outside pipe 12 since it passes through thedischarge part 13 having a narrower hole diameter. As the flow velocityincreases, the particle size of the oil spray is increased. When acertain flow velocity is secured, the oil spray can be formed into theoil droplet.

The oil spray is formed into the oil droplets in this way, because mostof the injected oil spray cannot be attached to the target object if theoil spray is injected in the form of fine oil spray or fume Therefore,for example, if the discharge part 13 is a drill that is attached viathe spindle with an oil hole of the machining center, the oil dropletsare discharged from the tip of the drill. Such oil droplets easily areattached to the target object, thus realizing a smooth process.

Furthermore, since the oil spray flowing into the spindle with an oilhole from the spray feeding pipe 12 has a fine particle size asmentioned above, it is hardly effected by the centrifugal force by thehigh-speed rotation of the spindle. Thus, it is possible to prevent theoil spray from being attached to the wall face of the oil hole.

Herein, the function of the gas discharge nozzle 3 is explained. Asmentioned above, after the oil spray passes through the discharge part13 having a narrower hole diameter, its flow velocity is increased. Theflow velocity is increased as the internal pressure of the container 1is higher. The internal pressure of the container 1 is also dependentupon the diameter of the discharge port 13. As the hole diameter of thedischarge part 13 is smaller, the internal pressure of the container 1is increased.

Therefore, for example, if the hole diameter of the discharge part 13 islarger than the predetermined diameter, it is not possible to secure thesufficient flow velocity, and thus the particle size of the oil spray isnot increased sufficiently, which may lead to the case where the oilspray cannot be converted into the effective oil droplets.

In this case, as in most practical cases, it is impossible to replace atool used as the discharge part 13 by a tool having an appropriatedischarge port. Furthermore, the spray injection nozzle 2 has a smalleffective cross-sectional area because it is provided for producingspray. Therefore, there is a limitation in order to increase thepressure of the injection gas.

In this case, the gas injection nozzle 3 is used. The gas injected fromthe gas injection nozzle 3 can enhance the internal pressure of thecontainer 1. Thus, it is possible to secure the flow velocity of the oilspray at the final exit portion. Since the gas injection nozzle 3 aimsat only supplying gas, it is possible to increase the effectivecross-sectional area as compared with the gas tube 6 of the sprayinjection nozzle 2, thus to extend the variable range of the pressure ofthe discharge gas sufficiently.

As mentioned above, even if the device is an oil supply device includingonly the oil spray from the spray injection nozzle 2, the device canfunction as an oil supply device.

However, in some cases of, for example, fast-speed and heavy cuttingprocess, etc., a larger amount of oil supply is required.

Furthermore, the pressure of injected gas from the gas injection nozzle3 increases the internal pressure of the container 1, thus to secure theflow velocity necessary to forming the oil spray into oil droplet at thefinal exit part. However, in this case, the amount of the oil spray ofthe container 1 is reduced at the same time. This is caused by thereduction of the gas flow rate for producing oil spray because the gasinjection from the gas injection nozzle 3 increase the internal pressureof the container 1, so that the difference between the discharge gaspressure from the gas tube 6 and the internal pressure of the container1 is reduced.

In such a case, the under-liquid nozzle 4, which is immersed in the oil11, is responsible for increasing the internal pressure of the container1 and increasing the amount of the oil spray inside the container 1. Asmentioned above, gas injected from the under-liquid nozzle 4 allows theoil spray from the liquid surface of the oil 11 to spray and diffuse.

By injecting gas from the under-liquid nozzle 4, the internal pressureof the container 1 is increased. At the same time, it is possible toproduce the oil spray in addition to the oil spray from the sprayinjection nozzle 2. Consequently, it is possible to compensate thereduction of oil spray from the spray injection nozzle 2 due to theincrease of the internal pressure of the container 1.

In the other words, it is possible to minimize the reduction of theamount of the oil spray in the container 1 by supplying the gas from theunder-liquid nozzle 4 while securing the flow velocity necessary forforming the oil spray into oil droplets at the final exit part.

In this embodiment, it is possible to increase the internal pressure ofthe container 1 by supplying the gas from the under-liquid nozzle 4, sothat the device can be used while stopping the gas injected from the gasinjection nozzle 3. When using the gas injected from the gas injectionnozzle 3 together, it is possible to extend the variable range of theinternal pressure of the container 1. Therefore, when the necessaryinternal pressure of the container 1 is secured, the gas device may notbe provided with the injection nozzle 3.

Furthermore, in this embodiment, when the injection pressure from theunder-liquid nozzle 4 is set to be constant by using a regulator or thelike, even if the tool such as a tip drill, etc. is replaced, fineadjustment in accordance with the change in the cross sectional area ofthe exit part is not required. For example, when the cross sectionalarea of the exit part becomes narrower, and the internal pressure of thecontainer 1 becomes a constant value or more, gas supplied from theunder-liquid nozzle 4 stops, so that unnecessary gas supply can beinhibited. In this case, only the oil spray from the spray injectionnozzle 2 can be injected into the container 1.

On the contrary, when the internal pressure of the container 1 is lowerthan a certain value, the gas is supplied from the under-liquid nozzle 4in accordance with the difference between the supplying pressure fromthe under-liquid nozzle 4 and the internal pressure of the container 1,and thus the necessary pressure of the container 1 can be secured.

Furthermore, in this embodiment, it is possible to produce oil spray bythe gas supplied from the under-liquid nozzle 4, in addition to the oilspray from the spray injection nozzle 2. Therefore, as compared with thecase of injecting the same amount of oil spray only from the sprayinjection nozzle 2, the work of the oil pump 10 can be reduced.

Furthermore, in order to produce the oil spray from the spray injectionnozzle 2, it is necessary to perform a preliminary run until oil issupplied from the oil pump 10 to the tip 6 a of the nozzle. The same istrue in the case where a siphon tube is used for supplying oil. When theoil spray is produced by the gas injected from the under-liquid nozzle4, oil spray is produced from the liquid surface right after the gas isinjected. Thus, the preliminary run is not required.

Furthermore, the amount of filled oil (liquid surface) is above theinjection port of the under-liquid nozzle 4, and oil spray is producedsurely. Therefore, it is possible to check whether the oil spray isproduced or not from the outside of the container by the use of, forexample, a float level switch.

Furthermore, it is possible to check the gas discharge pressure of thecontainer 1 by providing a pressure switch. From the discharge pressure,the virtual flow velocity of the oil spray at the exit part can becalculated, and thus the effectiveness of the oil spray state isdetermined.

In this embodiment, the case where both the oil spray from the sprayinjection nozzle 2 and gas injected from the under-liquid nozzle 4 aresupplied was explained. However, depending upon the application of use,the device without a spray injection nozzle can be employed. In such adevice, an oil pump is not necessary, and its maintenance need not becarried out.

Furthermore, the spray feeding outside pipe 12 is not necessarily singlebut a plurality of branched pipes 12 can be connected. In this case, itis possible to spray liquid to several places by using one device.

Furthermore, there is no limitation to the shape of the container aslong as the container is designed by taking the improvement of themerchantability, easiness in manufacture, maintenance property, and thelike. The shape is not necessarily limited to the circular but aprismatic shape also can be employed. For example, when themerchantability is important, for example, a box shaped tank may beemployed.

Second Embodiment 2

The device of Embodiment 2 is the same as that of Embodiment 1. Thedevice of Embodiment 2 is characterized by the relationship between thetip portion of the spray injection nozzle 2 and the internal wall faceof the container 1. With such a device of Embodiment 1, the lengthbetween the tip portion of the spray injection nozzle 2 and the tipportion of the spray feeding pipe 5 is set to be sufficiently long sothat, it is securely possible to drop the oil spray having a largeparticle size or oil droplets onto the liquid surface.

The device of Embodiment 2 is effective in a case where the container isrelatively small and the sufficient length between the tip portion ofthe spray injection nozzle 2 and the tip portion of the spray feedingpipe 5 cannot be obtained.

FIG. 2 is a horizontal cross sectional view showing a liquid spraydevice according to Embodiment 2. The tip portion of the spray injectionnozzle 2 is located so that most of injected flow amount strikes theface of the inner wall 1 a before being fed to the spray feeding pipe 5.In other words, most of injected spray flow amount from the sprayinjection nozzle 2 strikes the face of the inner wall 1 a withoutpassing through the center of the container 1 (shown by an arrow b).

Most of the fine oil spray is not attached to the wall face whenstriking the wall face, while oil spray having a large particle size oroil droplets is attached easily to the wall face. As the particle sizeof the oil spray increases, it tends to be attached to the wall face. Inparticular, oil droplets further tend to be attached to the wall face.Furthermore, the oil spray having a large particle size or oil dropletis attached to the inner wall face 1 a while circulating along the innerwall face 1 a in the direction shown by an arrow c after striking theinner wall face 1 a.

Therefore, among the injected spray flow amount from the spray injectionnozzle 2, most of the oil spray having a large particle size or oildroplets is attached to the inner wall face 1 a. Moreover, most amountof the oil spray having a large particle size or oil droplets flowing inthe air inside the container 1 without being attached to the face of theinner wall 1 a drops by gravity. Therefore, it is possible to preventthe oil spray having a large particle size or oil droplets from beingfed to the spray feeding pipe 5.

Moreover, the location relationship between the tip portion of the sprayinjection nozzle 2 and the opposing inner wall face 1 a is notparticularly limited as long as most of the injected spray flow strikesthe inner wall face 1 a directly before being fed to the spray feedingpipe 5. The injected spray flow may strike vertically with respect tothe inner wall face 1 a or may strike obliquely to the inner wall face 1a.

Furthermore, the case where the injected spray flow is allowed to strikethe inner wall face in the container was explained. A special wall facemay be provided, separately.

The device having a basic structure according to Embodiment 1 wasexplained. The same effect can be obtained with a device without havingan under-liquid nozzle or a gas injection nozzle.

Embodiment 3

The device according to Embodiment 3 is the same as that of theEmbodiment 1 except for the location relationship between the tipportion of the spray injection nozzle and the liquid surface of oil.

FIG. 3 is a vertical cross sectional view showing a liquid spray deviceaccording to Embodiment 3. The device of FIG. 3 is the same as that ofFIG. 1 except for the locations of the spray injection nozzle 2 and thegas injection nozzle 3. Therefore, the part such as a gas circuit etc.,is not shown herein. The tip portion of the spray injection nozzle 2 isdirected to the liquid surface side of the oil 11. The length betweenthe tip and the liquid surface is made to be close so that the spoutingof the oil 11 from the liquid surface can be prevented. Therefore, mostof the injected spray flow from the spray injection nozzle strikes theliquid surface directly before being fed to the spray feeding pipe 5.

Fine oil spray is hardly absorbed into the liquid surface even if itstrikes the liquid surface and flows in the container 1. The oil sprayhaving a large particle size or oil droplets is absorbed easily into theface of the liquid surface when it strikes the liquid surface not onlydue to dropping by gravity but also because the injection direction istoward the liquid surface side. Therefore, upon striking the liquidsurface, they likely to be absorbed there. As the particle size of theoil spray is larger, it tends to be absorbed to the liquid surface. Inparticular, oil droplets further tend to be attached to the oil surface.

Therefore, most of the injected spray flow from the spray injectionnozzle 2, oil spray having a large particle size or oil droplets, isabsorbed into the oil 11 without being fed to the spray feeding pipe 5.Therefore, it is possible to prevent from the oil spray having a largeparticle size or oil droplets from being fed to the spray feeding pipe5.

Similar to Embodiment 2, the device of this embodiment is effective in acase where the container is relatively small and the length between thetip portion of the spray injection nozzle 2 and the tip portion of thespray feeding pipe 5 cannot be obtained.

Moreover, the location relationship between the tip portion of the sprayinjection nozzle 2 and the opposing liquid surface is not particularlylimited as long as most of the injected spray flow from the sprayinjection nozzle 2 strikes the liquid surface directly before being fedto the spray feeding pipe 5. For example, the injected spray flow maystrike vertically with respect to the liquid surface or may strikeobliquely with respect to the liquid surface.

The device having a basic structure according to Embodiment 1 wasexplained. The same effect can be obtained by a device without having anunder-liquid nozzle or a gas discharge nozzle.

Embodiment 4

Embodiment 1 describes the example in which oil is supplied to the sprayinjection nozzle by an oil pump. In Embodiment 4, the siphon method isemployed instead of using the oil pump. FIG. 4 is a vertical crosssectional view showing a liquid spray device according to Embodiment 4.The device shown in FIG. 4 is the same as that of Embodiment 1 exceptthat the oil supply method employs the siphon method. Therefore, a gascircuit of the gas discharge nozzle 3 and the under-liquid nozzle 4 isnot shown herein.

The siphon tube 18 and gas tube 19 are connected to the spray injectionnozzle 17. The gas tube 19 is connected to the air source 8 and the flowrate can be regulated by the flow rate regulating valve 9 d. Inside thespray injection nozzle 17, gas supplied from the gas tube 19 producesthe difference between the pressure inside the nozzle and internalpressure of the container.

Therefore, the oil 11 is siphoned up from the lower end of the siphontube 18 into the spray injection nozzle 17 where the oil and gassupplied form the gas tube 19 are mixed, and thus oil spray is producedand injected into the container 1. In the middle of the siphon tube 18,by providing a throttling valve such as a needle valve, it is possibleto regulate the flow rate of oil.

In this embodiment, a gravitational method may be employed instead ofthe siphon method. In the case of employing the gravitational method, anoil tank is provided separately and oil is supplied to the tube bydropping the oil in the tube by gravity. Also in this case, the oil pumpis not necessary.

Embodiment 5

FIG. 5 is a vertical cross sectional view showing a liquid spray deviceaccording to Embodiment 5. Detailed explanation of the same parts as inFIG. 1 is not repeated herein by giving the same remarks. Inside thecontainer 1, a dome member 20 is provided that opens downward. The sprayinjection nozzle 2, a tip of which faces the inner wall face 20 a, islocated at the side of the inner wall face 20 a of the dome member 20.

Similar to Embodiment 1, oil spray is injected into the container 1 fromthe nozzle tip portion 6 a of the spray injection nozzle 2. As explainedin Embodiment 2, fine oil spray is hardly attached to the wall face evenif it strikes the wall face. On the other hand, the oil spray having alarge particle size or oil droplets is attached to the wall face easilywhen striking the wall face.

Therefore, of the injected spray flow from the nozzle tip portion 6 a,which strikes the inner wall face 20 a, most of the fine oil spray movesdownward along the inner wall face 20 a without being attached to theinner wall face 20 a (in the direction shown by arrows d and e) and thenmoves toward the spray feeding pipe 5 (in the direction shown by anarrows f, g and a).

On the other hand, some of the oil spray having a large particle size oroil droplets strikes the inner wall face 20 a and is attached to theinner face 20 a. And some of it is attached to the inner wall face 20 awhile moving along the inner wall face 20 a in the direction shown byarrows d and e. Furthermore, after they are attached to the inner wallface 20 a, some of them drop by gravity and some drop toward the oilsurface side of the oil 11 by self-weight and flow in the directionshown by the an arrows d and e so as to be pushed down.

Namely, most of the fine oil spray flows toward the upper space of thedome member 20. Most of the oil spray having a large particle size oroil droplets drop toward the lower space, that is, the side of theliquid surface of the oil 11 without flowing to the upper space insidethe container. A large quantity of the upflow into the upper spaceinside the container 1 strikes a flange 21 provided along the inner wallface 20 a.

Therefore, even if the upflow includes oil spray having a large particlesize or oil droplets, it strikes and is attached to the flange 21. Inother words, the flange 21 functions as thoroughly preventing the oilspray having a large particle size or oil droplets from feeding into thespray feeding pipe 5.

As mentioned above, since almost all of the oil spray which reaches theupper space is fine oil spray, the tip of the feeding port injectionport of the spray feeding pipe 5 is not particularly limited as long asit is located in the upper space of the container. For example, theinjection port may be directed downward or side-to-side, or may be aninclined face.

Furthermore, when oil is filled from the oil supply port 15, if oilremains on the outer wall face 20 b of the dome member, the remainingoil is fed to the spray feeding pipe 5 together with upflow. In oneexample of dome member 20 shown in FIG. 5, an external wall face 20 bhas an inclined face from the top to the lower side. Furthermore, thisinclined face is connected to the vertical face. Therefore, even if theoil is filled from the oil supply port 15, the oil drops along the domemember 20 to the liquid surface. Therefore, it is possible to preventthe filled oil from being fed to the spray feeding pipe 5.

In the above-mentioned explanation, the example is described in whichthe tip portion 6 a of the spray injection nozzle 2 is located at theside of the inner wall face 20 a of the dome member 20. However, theembodiment may be provided in which the nozzle tip portion 6 a may belocated in the upper side of the dome member 20 so that the nozzle tipportion 6 a faces the external wall face 20 b. In this case, most of theoil spray having a large particle size or oil droplets is attached tothe outer wall face 20 b when it strikes thereto, or drops toward theside of the liquid surface of the oil 11 along the external wall face 20b. Therefore, the oil spray having a large particle size or oil dropletshardly flows upwardly. Thus, most of the oil spray fed to the sprayfeeding pipe 5 is fine oil spray.

Furthermore, similar to the case where the nozzle tip portion 6 a islocated at the side of the inner wall face 20 a, by providing the flange21, it is thoroughly possible to prevent the oil spray having a largeparticle size or oil droplets from entering the spray feeding pipe 5.

Moreover, the shape of the dome member 20 is not limited to the exampleshown in FIG. 5, and other shapes may be employed, as long as the domemember opens downward. For example, a hemispherical shape, a conicalshape, cylindrical shape or prismatic shape or combination thereof maybe employed.

Furthermore, instead of a dome shape, a planar shape may be employed if,for example, the oil supply port 15 is provided in the lower part fromthe plane member so that filled oil does not reside on the plane.

Embodiment 6

FIG. 6 is a vertical cross sectional view showing a liquid spray deviceaccording to Embodiment 6. The lower part has the same configuration asthat of Embodiment 5 shown in FIG. 5, so the part is not shown herein.

In Embodiment 6, the tip portion of the spray injection nozzle 2 isdirected to the side face 22 a of the dome member 22. Therefore, most ofthe injected spray flow strikes the side face 22 a and circulates alongthe side face 22 a (in the direction shown by arrows h, i and j). Theoil spray having a large particle size or oil droplets is attached notonly to the side face 22 a when striking the side face 22 a but alsoattached to the side face 22 a while circulating along the side face 22a. Furthermore, the oil spray attached to the side face 22 a drops tothe liquid surface due to the circulation flow in addition to the selfweight.

Therefore, similar to Embodiment 5, most of fine oil spray flows in theupper space of the dome member 22 (in the direction shown by an arrowk). However, most of the oil spray having a large particle size or oildroplets drop toward the side of the liquid surface of the oil 11without flowing into the upper space of the container.

Embodiment 7

FIG. 7 is a vertical cross sectional view showing a liquid spray deviceaccording to Embodiment 7. The lower part of this drawing is the same asthat shown in FIG. 5 and so is not shown herein. The basic operation ofthe liquid spray device according to Embodiment 7 is the same as that ofEmbodiment 5. However, in the liquid spray device of Embodiment 7, theuser can select the way of using from the following two ways: that is,the way of taking most of the injected spray flow from the sprayinjection nozzle 2 out of the container after it strikes the wall face;and the way of taking most of the injected spray flow from the sprayinjection nozzle 2 directly out of the container.

In the case of taking the injected spray flow from the spray injectionnozzle 2 directly to the outside of the container, the oil spray havinga large particle size or oil droplets also is taken out together. Thus,such way of using is useful for the case where the classification of theparticle size of the oil spray is not required and can be performed byopening and closing a valve 25 connected to a discharge flow feedingpipe 23 and a valve 26 connected to a spray feeding pipe 24.

In the case of taking the injected spray flow from the spray injectionnozzle 2 directly to the outside of the container 1, the valve 25 isopened and the valve 26 is closed. Thereby, most of the discharge flowfrom the spray injection nozzle 2 is fed to the discharge flow feedingpipe 23.

When the discharge flow from the spray injection nozzle 2 is taken outto the outside of the container after classifying the particle size ofthe discharge flow, the valve 26 is opened and the valve 25 is closed.This operation is the same as that in Embodiment 5, and fine oil sprayis fed to the spray feeding pipe 24.

Furthermore, depending upon the application of use, both valves 25 and26 may be opened. In this case, the discharge flow from the sprayinjection nozzle 2 directly is fed to the spray feeding pipe 23. Thus,fine oil spray is fed to the spray feeding pipe 24. Therefore, with theliquid spray device of this embodiment, it is possible to use the devicein different manners depending upon target objects which oil issupplied.

In the above-mentioned explanation, the nozzle tip portion 6 a of thespray injection nozzle 2 is located at the side of the inner wall faceof the dome member 20 is explained. However, the configuration is notnecessarily limited to this. For example, the nozzle tip portion 6 a islocated at the upper side of the dome member 20 and located so that theexternal wall face of the tip of the nozzle 6 a faces the external wallface of the dome member. In this case, the discharge flow feeding pipe23 is located inside the dome member 20. Consequently, the injectionspray flow flowing into the injected spray flow feeding pipe 23 from thenozzle tip portion 6 a is located inside the dome member 20 and movesdownward inside the discharge flow feeding pipe 23.

Moreover, in Embodiments 5 to 7, the under-liquid nozzles are notprovided. However, the under-liquid nozzle may be provided. Thereby,similar to Embodiments 1 to 4, it is possible to increase the flowvelocity of spray at the spray injection path exit part and to increasethe amount of spray.

Moreover, in Embodiments 5 to 7, the case where the oil is fed to thespray injection nozzle 2 by the use of oil pump is explained. However,as explained in Embodiment 4, the siphon method or gravitation methodmay be employed.

Embodiment 8

According to each of the above-mentioned Embodiments, the internalpressure of the container can be regulated, for example in the exampleshown in FIG. 1, by means of gas flow rate regulating valves 9 a, 9 band 9 c. Furthermore, as explained in Embodiment 1, in a case where theunder-liquid nozzle is used in addition to the spray injection nozzle,even if the cross sectional area of the exit of the discharging port ischanged, the internal pressure is regulated automatically. The device ofthis Embodiment is not designed so that the internal pressure iscontrolled directly, but the internal pressure of the containerconsequently is maintained constant.

In the below mentioned Embodiments 8 to 10, regardless of the presenceof the under-liquid nozzles, it is possible to keep the internalpressure of the container constant. In other words, by directlycontrolling the internal pressure of the container by the use ofpressure controlling means, the internal pressure of the containerautomatically is controlled to be constant although the cross sectionalarea of the exit of the discharging port is changed.

If the internal pressure of the container is constant, the differencebetween the primary pressure and the internal pressure of the containerbecomes constant. Therefore, the flow velocity of the gas for producingspray in the container becomes constant. As a result, stable sprayproduction can be performed. Furthermore, also at the discharging portwhose cross sectional area of exit is narrow, constant flow velocity canbe secured, so that spray is converted into oil droplets and the oildroplets can be injected.

FIG. 8 shows a pressure control circuit according to Embodiments 8 to10. In FIG. 8, an example in which the gas injection nozzle to thecontainer 1 is only the under-liquid nozzle is simplified, but thestructure of the container 1 may be any structure of the above-mentionedEmbodiments. In other words, the gas supply nozzle to the container 1may be formed of the spray injection nozzle, the under-liquid nozzle andthe gas discharge nozzle, or may be formed of the spray injection nozzleand the under-liquid nozzle, or may be formed only of the gas dischargenozzle.

In Embodiment shown in FIG. 8(a), a pressure regulating valve is used asa pressure control means. In this Embodiment, pressure is regulated bymechanical control and it is possible to use a reducing valve capable ofopening and closing valve by the compression spring force. The primarysupply gas from the gas source 8 is fed to the container 1 via apressure regulating valve 27. When the cross sectional area of the exitbecomes small by replacing the discharging part 13, the internalpressure of the container 1 is increased. If a secondary pressure(pressure of the side of the container 1 with respect to the pressureregulating valve 27) is not less than the set value, gas flowing by apilot circuit activates the pressure regulating valve 27, thus to stopsupplying gas.

When the pressure in the container 1 is reduced to the predeterminedvalue, the pressure regulating valve 27 is opened by the restoring forceof spring, and thus the gas is supplied again. Therefore, even if thecross sectional area of the exit of the discharge part 13 is changed,the pressure in the container 1 can be maintained in the constant rangeby opening and closing the pressure regulating valve 27. According tothe mechanical control of this embodiment, since the structure issimple, the cost can be reduced and attachment operation is performedeasily.

Furthermore, it is preferable that the pressure regulating valve 27 canregulate the set value by regulating the spring pressure. For example,in order to increase the flow velocity at the injected spray part, theset value is increased. In this case, the difference between the primarypressure and the internal pressure of the container is reduced, so thatit is disadvantageous in producing oil spray stably, but the amount ofinjected spray flow is increased. Therefore, in the cutting process, itis effective in the case where removing cutting powder is more importantrather than spraying oil. Furthermore, the device of this embodiment canbe used for removing cutting powder by air blowing after the cuttingprocess, if necessary, by regulating the set value.

Embodiment 9

In Embodiment 9, a pressure control circuit shown in FIG. 8(b)electrically controls the internal pressure of the container 1. In thisembodiment, an electromagnetic valve 28 and a pressure switch 29 areused as a pressure control means. The pressure switch 29 includes apressure detecting part. The primary supply gas from the gas source 8 isfed to the container via the electromagnetic valve 28.

Secondary pressure (the internal pressure of the container 1) isdetected by the pressure switch 29. When the secondary pressure is abovethe set value (upper limit of the set value), the pressure switch 29operates, and thereby the electricity is carried to a coil part of theelectromagnetic valve 28 (or electricity is stopped carrying), and thusthe electromagnetic valve 28 is closed and gas supply is stopped.

When the internal pressure of the container 1 drops to the predeterminedvalue (lower limit of the set value), the pressure switch 29 operates,and thereby the electricity is stopped being carried to a coil portionof the electromagnetic valve 28 (or electricity is carried), and thusthe electromagnetic valve 28 is opened and gas supply is resumed.Therefore, the internal pressure of the container automatically iscontrolled to be within the constant range by opening and closing theelectromagnetic valve 28 although the cross sectional area of the exitof the discharge part 13 is changed. According to the electric controlof this embodiment, as compared with the mechanical control, operationis more accurate and accuracy of pressure control can be improvedalthough the cost is high.

Furthermore, it is preferable that the pressure switch 29 has severalcombinations, in particular two combinations, of different set values ofupper and lower limits. With such a pressure switch, the device can beused for two kinds of applications of use, for example for cutting andair blowing. In setting the pressure for the cutting process, thepressure is set so that spray can be attached to the tool or targetobject. In setting the pressure for the air blowing process, thepressure is set so that the flow velocity, which is sufficient to blowoff cutting powder produced during the cutting process, is secured.

According to such a pressure setting, during the cutting process, theset value for the cutting process is used, and after the cuttingprocess, the set value for air blowing by changing the pressure switchto blow off cutting powder is used.

Furthermore, it is not always necessary to switch the set value betweenthe pressure for cutting process and the pressure for air blowing afterthe cutting process. Two pairs of set values are made to be the setvalue for cutting process. For example, a pair of set value is made tobe the set value, which is mainly intended to the set value for sprayingamount and another pair of the set values is made to be set value forincreasing the flow rate of gas at the discharge part. The set value forincreasing the flow rate of gas results in reducing the amount of spray.This value is useful in the case where removing cutting powder is moreimportant than spraying to the cutting part.

As one example of Embodiment 9, when the internal pressure of thecontainer is determined with the primary pressure of 0.6 MPa, the setvalue for operating the pressure switch of 0.3 MPa, the hole diameter ofthe final exit part changing in the range from 1.0 to 4.0 mm, thevariation of the internal pressure of the container is small. Thus, itis confirmed that the internal pressure of the container is stable.

Embodiment 10

FIG. 8(c) shows a pressure control circuit according to Embodiment 10.The pressure control circuit electrically controls the internal pressureof the container 1 and uses an electromagnetic valve 30, a pressuresensor (not shown) and a control part 31 as a pressure control means.The device of this embodiment is the same as that of Embodiment 9 inthat electric control is performed by opening and closing theelectromagnetic valve, but different from the device of Embodiment 9 inthat the pressure switch is not used and the control part is used.

The primary supply gas from the gas source 8 is fed to the container 1via the electromagnetic valve 30. The secondary pressure (internalpressure of the container 1) is detected by the pressure sensor andconverted into the electric (voltage or current) signal. This electricsignal is input into the control portion 31 and the difference withrespect to the set value (voltage value or current value correspondingto the set voltage) is processed arithmetically.

The result of the arithmetic process shows that when the input signal isthe set value (upper limit set value) or more, the control part 31 sendsa signal to close the valve to the electromagnetic valve 30. As aresult, electricity is carried to (or electricity is stopped fromflowing to) the coil part of the electromagnetic valve 30, so that theelectromagnetic valve 30 is closed, and thus gas supply is stopped.

When the internal pressure of the container 1 is dropped to thepredetermined value lower limit set value), the control part 31 sends asignal to open the valve to the electromagnetic valve 30. As a result,flow of electricity is stopped (or carrying electricity is performed) tothe coil part of the electromagnetic valve 30, so that theelectromagnetic valve 30 is opened, and thus gas supply resumes.

Therefore, the internal pressure of the container 1 is maintained in theconstant range by opening and closing the electromagnetic valve 30although the cross sectional area of the exit of the discharge part 13is changed. With such an electric control, the electric signals obtainedby a pressure sensor are processed arithmetically so as to send acommand to the electromagnetic valve 30 based on the signal obtained bythe arithmetic processing. Consequently, necessary voltage valueoptionally can be set by, for example, internal voltage changing volume.In Embodiment 10, a control equipment or control software is required,so that the cost is higher as compared with the device described inEmbodiment 9. However, the device of this embodiment can perform moreaccurate pressure control.

In the above-mentioned explanation, gas supply is performed or gas isstopped by directly opening and closing the electromagnetic valve 30,but the configuration is not necessary limited to this. For example, avalve is provided in the gas supplying path to the container 1, and thisvalve may be opened and closed by the electromagnetic valve. Forexample, an electromagnetic valve is provided in a path that is branchedwith respect to the gas supplying path and when the detected pressure isabove the set value (upper limit of the set value) or more, the controlvalve 31 sends a signal to close the electromagnetic valve. Thereby, thegas supply from the electromagnetic valve to the valve of the gassupplying path is stopped and the valve of the gas supply path isclosed.

When the detected pressure drops to the predetermined value (lower limitset value), the control part 31 produces a signal to open theelectromagnetic valve. Thereby, gas from the electromagnetic valveresumes so as to open the valve of the gas supply path. The case wasexplained, in which when the valve of the gas supply path is closed, theelectromagnetic valve is closed; and when the valve of the gas supplypath is opened, the electromagnetic valve is opened. However, theconfiguration is not necessarily limited to this. The configuration inwhich when the electromagnetic valve is closed, the valve of the gassupply path is opened, and while the electromagnetic valve is opened,the valve of the gas supply path is closed may be employed. In this casethe command signal is reversed.

As one example of Embodiment 10, when the internal pressure of thecontainer is determined with the primary pressure of 0.6 MPa, the setvalue of 0.3 MPa, the hole diameter of the final exit part changing inthe range from 1.0 to 5.0 mm (when it is 5.0 mm, the number of thedischarging ports is two), the variation of the internal pressure of thecontainer is smaller than that in Embodiment 9. Thus, it is confirmedthat the internal pressure of the container is stable.

Furthermore, in the electric control according to Embodiment 10, byswitching the set values, it is possible to use for the applications ofuse in accordance with set values, for example for cutting purpose andfor air blowing.

Embodiment 11

Embodiment 10 shows the case where the pressure is detected by thepressure sensor in the container 1 . FIG. 9 is a pressure controlcircuit according to Embodiment 11. In Embodiment 11, the pressure isdetected in the gas supply path between the electromagnetic valve 30 andthe container 1. The pressure detected in the gas supply path betweenthe electromagnetic valve 30 and the container 1 is converted into theelectric (voltage or current) signals. The electric signals are inputinto the control portion 31 via a path 32.

Furthermore, the pressure detection by the pressure sensor may beperformed in the spray feeding outside pipe 12 between the container 1and the discharge part 13. The arrangement of the pressure sensor iseffective for the case where the feeding outside pipe 12 is too long, orit curves complicatedly, and thus the pressure loss is large.

In the above, the device provided with the pressure control means wasdescribed. For enhancing the accuracy of the internal pressure,Embodiments 10 and 11 are preferred. However, in the case where the somevariation is allowed or complicated set conditions are not required,Embodiments 8 and 9 are suitable from the viewpoint of cost orsimplification of equipment.

Furthermore, in a case where a plurality of gas supply nozzles into thecontainer are present in Embodiments 8 to 11, it is necessary to provideat least one pipe path of each gas supply nozzle with a pressure controlmeans. However, a pressure control means may be provided for a pluralityof pipe paths.

Furthermore, oil supply is stopped as gas supply is stopped. With such acontrol, the life of the device having a movable part such as an oilsupply pump can be improved. For example, in a device where oil issupplied under pulse air pressure, a pulse generator that is a source ofthe pulse or the electromagnetic valve is stopped as the gas supply isstopped. Furthermore, in the device in which the oil is siphoned up, theoil supply is stopped with the valve incorporated into the oil supplypipe or by the gas flow generating the negative pressure is stopped.

EXAMPLE

In Example, a device additionally including a gas discharge nozzle andan under-liquid nozzle as shown in FIG. 1 in the device shown in FIG. 5was used. The tip of the spray feeding tube is connected to themachining center with the high speed revolution * center throughspecification. Furthermore, a nozzle is connected to this machiningcenter. The experiment was carried out under the following conditions.

Container: 4 inch stainless tube (outer diameter: 114.3 mm, wallthickness: 2.1 mm, height: 250 mm)

dome member: 3 inch welded cap (outer diameter: 89.1 mm)

spray feeding tube: nylon tube (inner diameter: 9 mm×outer diameter 12mm)

under-liquid nozzle: discharging area 3.14 mm²

primary supply air pressure: 0.6 MPa (about 6 kg/cm²)

spray injection nozzle: discharging area 2.26 mm² (diameter 1.7 mm)

main axis revolution number: 14000 rpm

In comparative example, the case where the air injected from theunder-liquid nozzle was stopped and the case where air injected onlyfrom the under-liquid nozzle were examined. Table 1 shows the results.

TABLE 1 Co. Co. Ex. Co. Ex. Ex. 1 2 3 Ex. 1 Ex. 2 Flow rate frominjection 65 52 0 52 55 nozzle (NL/min) Flow rate from under- 0 0 110 4035 liquid nozzle (NL/min) Flow rate from gas 0 60 0 0 20 injectionnozzle (NL/min) Inner pressure of 0.12 0.35 0.35 0.32 0.35 container(MPa) State at Exit Fume Oil Oil Oil Oil droplet droplet droplet dropletCo. Ex. = Comparative Example, Ex. = Example

In Comparative Example 1, injection was stopped both from theunder-liquid nozzle and the gas discharge nozzle. As a result, theinternal pressure of the container was deficient, so that oil spraycould not be formed into oil droplets at the tip of the nozzleconnecting to the machining center and only the fume type oil could betaken out.

Comparative Example 2 was confirmed while the air flow rate from the gasdischarge nozzle was increased. The internal pressure of the containerwas gradually increased, and when the air flow rate reached 60 NL/min,oil spray could be taken out in the form of oil droplets from the nozzleconnecting to the machining center. This shows that as explained inEmbodiment 1, air discharge from the gas discharge nozzle was effectivefor forming oil spray into oil droplets. Furthermore, as the internalpressure of the container was increased, the flow rate from the sprayinjection nozzle reduced by 20%. As compared with Comparative Example 1,the amount of oil spray injecting into the container was reduced.

In Comparative Example 3, air was injected only from the under-liquidnozzle. In this case, oil droplets could be taken out from the nozzleconnecting to the machining center. This shows that oil spray could beproduced by air injection from the stored oil.

In Example 1, air discharge from the gas discharge nozzle was stoppedand the air flow rate from the under-liquid nozzle was increased.Furthermore, the flow rate from the spray injection nozzle was set to be52 NL/min, which was the same as in Comparative Example 2. When the flowrate from the under-liquid nozzle was 40 NL/min, oil spray could betaken out in the form of oil droplet from the nozzle connecting to themachining center. Yet, visual observation showed that the flow amountwas increased as compared with Comparative Example 2. The results showsthat oil spray, which was produced from the liquid surface of oil,played a role as increasing the amount of the discharged oil droplet.

Example 2 was carried out while increasing the air flow rate from thegas discharge nozzle in the state of Example 1. When the air flow ratewas 20 NL/min, the internal pressure of the container became the same asthat of Comparative Example 2. In this state, the total flow rate (112NL/min) of Comparative Example 2 was substantially the same as the totalflow rate (110 NL/nub) of Example 2. However, the amount of oil dropletfrom the nozzle connecting to the machining center was larger in Example2 by visual observation. This shows that sufficient amount of oildroplets could be secured by adjusting the air flow rate both from theunder-liquid nozzle and from the gas discharge nozzle.

Industrial Applicability

As mentioned above, the liquid spray device of the present inventionpermits spraying liquid to the target object by feeding spray of thecontainer, so that the device can be used as a device for supplying acutting member of a machine tool, for example, a machining center, agrinding machine, a turning machine, or the like, with a cutting oil.

Furthermore, the cutting method of the present invention uses a deviceof spraying liquid to the target object by feeding the spray in thecontainer, so that it can be used for cutting method for processing thetarget object by using a machining center, a grinding machine, a turningmachine, or the like.

What is claimed is:
 1. A cutting device, comprising a container, a sprayinjection nozzle for injecting oil spray into the container, and a sprayfeeding path for feeding the oil spray in the container to an outside ofthe container, wherein a gas discharge nozzle is provided having a tipportion in the air within the container and discharging gas, whereinmost of the injected spray flow from the spray injection nozzle isallowed to strike a wall face in the container before being fed to thespray feeding path, and wherein the wall face is an inner wall face of adome member opening downward.
 2. The cutting device according to claim1, wherein an inside of the container is divided into an upper space anda lower space by the wall face, and the injection port of the sprayinjection nozzle is located in the lower space.
 3. The cutting deviceaccording to claim 1, wherein an inside of the container is divided intoan upper space and a lower space by the wall face, and the injectionport of the spray injection nozzle is located in the upper space.
 4. Thecutting device according to claim 1, further comprising a pressurecontrol means for keeping the pressure in the container constant in thepath for supplying the gas to the gas discharge nozzle.
 5. The cuttingdevice according to claim 1, wherein a tip-tapered discharge part isconnected to the tip of the spray feeding path.
 6. The cutting deviceaccording to claim 1, wherein gas and oil are fed to the spray injectionnozzle, and the spray is injected into the container by mixing the gasand the oil in the spray injection nozzle.
 7. The cutting deviceaccording to claim 6, wherein the oil stored in the container flows intoa liquid supply means and the oil discharged from the liquid supplymeans is fed to the spray injection nozzle.
 8. The cutting deviceaccording to claim 7, wherein the liquid supply means is an oil pump. 9.The cutting device according to claim 6, further comprising a pressurecontrol means for keeping the pressure in the container constant in apath for supplying the gas to the spray injection nozzle.
 10. A cuttingdevice, comprising a container, a spray injection nozzle for injectingoil spray into the container, and a spray feeding path for feeding theoil spray in the container to an outside of the container, wherein a gasdischarge nozzle is provided having a tip portion in the air within thecontainer and discharging gas, wherein most of the injected spray flowfrom the spray injection nozzle is allowed to strike a wall face in thecontainer before being fed to the spray feeding path, and wherein thewall face is an outer wall face of a dome member opening downward.
 11. Acutting device, comprising a container, a spray injection nozzle forinjecting oil spray into the container, and a spray feeding path forfeeding the oil spray in the container to an outside of the container,wherein a gas discharge nozzle is provided having a tip portion in theair within the container and discharging gas, wherein most of theinjected spray flow from the spray injection nozzle is allowed to strikea wall face in the container before being fed to the spray feeding path,and wherein the injected spray flow, after striking the wall face andbefore being fed to the spray feeding path, strikes another wall faceformed separately from the wall face.
 12. A cutting method, comprisingattaching a liquid spray device to an oil supplying part of a machinetool, the liquid spray device comprising a container, a spray injectionnozzle for injecting oil spray into the container, a spray feeding pathfor feeding oil spray in the container to an outside of the container,wherein a gas discharge nozzle is provided having a tip portion in theair within the container and discharging gas, wherein most of the sprayfrom the injection nozzle is allowed to strike a wall face in thecontainer before being fed to the spray feeding path, and wherein thewall face is an inner wall face of a dome member opening downward; andcutting a target object to be processed by supplying the spray to acutting member of the machine tool.
 13. The cutting method according toclaim 12, wherein the inside of the container is divided into an upperspace and a lower space by the wall face, in which the injection port ofthe spray injection nozzle is located in the lower space.
 14. Thecutting method according to claim 12, wherein the container is dividedinto an upper space and a lower space by the wall face, in which theinjection port of the spray injection nozzle is located in the upperspace.
 15. A cutting method, comprising attaching a liquid spray deviceto an oil supplying part of a machine tool, the liquid spray devicecomprising a container, a spray injection nozzle for injecting oil sprayinto the container, a spray feeding path for feeding oil spray in thecontainer to an outside of the container, wherein a gas discharge nozzleis provided having a tip portion in the air within the container anddischarging gas, wherein most of the spray from the injection nozzle isallowed to strike a wall face in the container before being fed to thespray feeding path, and wherein the wall face is an outer wall face of adome member opening downward; and cutting a target object to beprocessed by supplying the spray to a cutting member of the machinetool.
 16. A cutting method, comprising attaching a liquid spray deviceto an oil supplying part of a machine tool, the liquid spray devicecomprising a container, a spray injection nozzle for injecting oil sprayinto the container, a spray feeding path for feeding oil spray in thecontainer to an outside of the container, wherein a gas discharge nozzleis provided having a tip portion in the air within the container anddischarging gas, wherein most of the spray from the injection nozzle isallowed to strike a wall face in the container before being fed to thespray feeding path, and wherein the injected spray flow, after strikingthe wall face and before being fed to the spray feeding path, strikesanother wall face formed separately from the wall face; and cutting atarget object to be processed by supplying the spray to a cutting memberof the machine tool.
 17. A cutting device, comprising: a tool; and anoil supply system for the tool, including: a container; a sprayinjection nozzle for injecting oil spray into the container; and a sprayfeeding path for feeding the oil spray in the container to an outside ofthe container; wherein a gas discharge nozzle is provided having a tipportion in air within the container and discharging gas, wherein most ofthe injected spray flow from the spray injection nozzle is allowed tostrike a wall face in the container before being fed to the sprayfeeding path, and wherein the wall face is an inner wall face of a domemember opening downward.
 18. A cutting device, comprising: a tool; andan oil supply system for the tool, including: a container; a sprayinjection nozzle for injecting oil spray into the container; and a sprayfeeding path for feeding the oil spray in the container to an outside ofthe container; wherein a gas discharge nozzle is provided having a tipportion in air within the container and discharging gas, wherein most ofthe injected spray flow from the spray injection nozzle is allowed tostrike a wall face in the container before being fed to the sprayfeeding path, and wherein the wall face is an outer wall face of a domemember opening downward.
 19. A cutting device, comprising: a tool; andan oil supply system for the tool, including: a container; a sprayinjection nozzle for injecting oil spray into the container; and a sprayfeeding path for feeding the oil spray in the container to an outside ofthe container; wherein a gas discharge nozzle is provided having a tipportion in air within the container and discharging gas, wherein most ofthe injected spray flow from the spray injection nozzle is allowed tostrike a wall face in the container before being fed to the sprayfeeding path, and wherein the injected spray flow, after striking thewall face and before being fed to the spray feeding path, strikesanother wall face formed separately from the wall face.